Biology 1 final exam
what are the three components of the cell theory?
1) all living things are made from cells 2) cells are the basic units of life 3) cells come from other cells (biogenesis)
what important molecules does the nucleus contain?
DNA
what is a transgenic organism?
DNA from two sources
interphase is divided into what three phases?
G1 phase, S phase, and G2 phase
how did Pasteur settle the spontaneous generation argument
He put broth into a flask with a neck and showed that when the neck was on, the broth remained clear. when he broke the neck off, the broth became cloudy
what is an enzyme and what is the funtion?
a catalyst that speeds up a chemical reaction
the theory that new organisms come from existing organisms is called what?
biogenesis
manipulation of the genomes of plants, animals, or people with the goal of increasing their health or productivity is called?
biotechnology
the process by which a cell divided into two new daughter cells is called
cell division
what forms midway between the divided nuclei during cytokinesis in plant cells
cell plate
what structures do only plant cells contain?
cell wall, chloroplast, and vacuole
what are most plant cell walls made of?
cellulose
what structrures do only animal cells contain?
centrioles and lysosomes
each pair of chromatids is attached at an area called the?
centromere
at the beginning of cell division, each chromosome consists of two sister
chromatids
the visible material within the nucleus is called
chromatin or chromosomes
cytoplasm
clear fluid inside the cell
the process of allowing cells to reproduce in order to obtain a large number of identical cells is called?
cloning
Golgi body
closely stacked, flattened membrane sacs
pattern of inheritance in which both alleles contribute to the phenotype of the organism
co-dominant
what is homeostasis?
constant conditions that an organism needs to retain
chloroplast
contains clorophyll, a green pigment that traps energy from sunlight
chloroplast
contains inner membranes arranged in stacks of membranous sacs called grana
describe the function of the cell membrane
control what goes in and out of the cell, and protect and support the cell
when a variable is kept unchanged in an experiment, it is said to be
controlled
selective breeding
crossing dissimilar individuals to bring together the best of both organisms
guanine pairs with _
cytosine
phenotype
physical characteristics of an organism
plastids
plant organelles that store starches or lipids or that contain pigments
small circular forms of bacterial DNA are called?
plasmids
what is the condition of having many sets of chromosomes?
polyploidy
what is cytokinesis?
process of cytoplasm dividing into two daughter cells
what is diffusion?
process of particles moving from high concentration to low concentration
what is cell division?
process where cell divides into two daughter cella
what is meiosis?
process where the number of chromosomes per cell is cut in half through separation of homologous chromosomes in a diploid cell
mitochondria
produce a usable form of energy for the cell; uses energy from food to form high energy compunds
in what stage do the centrioles take up positions on opposite sides of the nucleus?
prophase
in what stage do the chromosomes become visible?
prophase
what is ATP used for
storing and releasing energy
what is an organelle?
structures that act like organs in the cell
in what stage does a nuclear envelope reform around each cluster of chromosomes?
telophase
in what stage does the nucleus become visible in each daughter nucleus?
telophase
In science, a hypothesis is useful only if it can be
tested
how did Rudolph Virchow summarize his years of work?
the Cell Theory
what is a cell?
the basic unit of life
inbreeding
the continued breeding of individuals with similar characteristics
Data
the information gathered from observation is called evidence or...
heterozygous
organisms that have two different alleles for the same trait
homozygous
organisms that have two identical alleles for a particular trait
adenine pairs with _ (DNA)
Thymine
thymine pairs with_
adenine
What did german scientist Theodor Schwann conclude?
all animals are made of cells
what did german botanist Matthias Schleiden conclude?
all plants are made of cells
what word describes different forms of a gene?
allele
in what stage do the chromosomes move to the poles?
anaphase
lysosome
digests excess or worn out cell parts, food particles, and invading viruses or bacteria
what word describes a cell that contains two sets of chromosomes?
diploid
what does a pedigree chart show?
family history
cell wall
firm, protective structure that gives the cell its shape in plants, fungi, most bacteria, and protists
ER
folded membrane that forms a network of interconnected compartments in the cytoplasm
what are sex linked genes?
genes on the x chromosome
genotype
genetic makeup of an organism
cytosine pairs with_
guanine
describe the function of the nucleus
holds the DNA for the cell
what are compound light microscopes?
microscopes that allow light to pass through the specimen
what causes a cell to shrink?
hypertonic solution
what causes a cell to swell
hypotonic solution
the period of growth in between cell divisions is called?
interphase
what does not change the shape of a cell?
isotonic solution
what causes osmosis?
isotonic solution, hypotonic solution, and hypertonic solution
what is important about a selectively permeable membrane?
it allows certain things to move across the membrane into the cell
describe the cytoplasm
it is the fluid in the cell
what is the difference between meiosis in male humans and meiosis in female humans?
males have 4 haploid cells, females have 1 haploid cell and 3 polar bodies
in what stage do the chromosomes line up across the center of the cell?
metaphase
when collecting data and doing experiments, what system of measurements do most scientists use?
metric system or SI
the division of the cell nucleus is called _ in body cells, but _ in reproductive cells
mitosis, cytokinesis
golgi body
modifies proteins chemically, then repackages them
the process by which certain bacteria can absorb nitrogen from the atmosphere and convert it to a form that may be used by plants is called?
nitrogen fixation
what is the cytoskeleton?
organelle in eukaryotes that maintain cell shape, move cell parts, and help the cell move
nucleus
organelle that manages cell functions in eukaryotic cells
define prokaryote and give an example
organism whose cell lack nuclei; bacteria
define eukaryote and give an example
organism whose cells contain nuclei; animals, plants, fungi, and protist
vacuole
provides temporary storage of food, enzymes and waste products
a new strand of DNA is formed when DNA fragments from different species of organisms are spliced together is called?
recombinant DNA
what si produced when DNA from two different sources are combined?
recombinant DNA
what is a molecule that cuts DNA molecules at a specific sequence of nucleotides?
restriction enzyme
what is the difference between rough ER and smooth ER
rough ER- covered in ribosomes and makes proteins smooth ER- no ribosomes and makes lipids
what is a hypothesis?
scientific explanation for an observation
what are gametes?
sex cells
describe the function of the cell wall
shape the cell and support and protect the cell
ribosomes
sites of protein synthesis
ribosome
small bumps located on the rough ER
what are variables in an experiment
something that is being tested
a fan like microtubule structure that helps to separate the chromosomes is called?
spindle fibers
the idea that life can arise from nonliving matter is called
spontaneous generation
what is biology?
the study of life
what are chromosomes?
thread like condensed DNA strands
what is a specific characteristic that varies from one individual to another?
trait
condition where and individual has three copies of a chromosome?
trisomy
adenine pairs with_ (RNA)
uracil